Ventilator attachment



F. 0. SMITH.

- VENTILATOR ATTACHMENT.

APPLICATION FILED JAN.25. 1917-.

Patented Sept. 14,1920.

Es: INVENTOR:

FRANK c. SMITH ATTORNEYS WITNES FRANK 0. SMITH, or MINNEAPOLIS, 'MrNNnso'rA.

VENTILATOR AT'PACHMENT.

To all whom it may concern is it known=that I, FRANK C.- SMITH, a citizen of the United States, resident of Minneapolis, county of Hennepin, State; of

-Minnesota,-ha ve invented cer'tainnew and useful Improvements in Ventilator Attachments', of which the'following is a specification.

The object of my invention is to provide an attachment for a ventilator or flue which will operate as a means for in'creasingthe draft and hastening the discharge of the currents of air from the ventilator. V

A further object is to provide a ventilator attachment of comparatively simple construction and one which can be applied to an ordinary ventilator at a comparatively small expense.

'A further object is to provide an'attachment which may be used in. connection with a chimney flue. Y

The invention consists generally in various constructions and combinations, all as hereinafter described and particularly pointed out in the claim.

In the accompanying drawings forming part of this specification,

Figure 1 is an elevation, partially in section, of the upper portion of a ventilator with my invention applied thereto,

Fig. 2 is a sectional view, showing the po- 7 sition of the attachment on the ventilator and themeans for imparting arotary movement to the currents of air,

Fig. 3 is a view looking at the exit of the ventilator, showing the narrow air passages between its walls and the wall ofthe attachment.

In the drawing, 2 represents the upper portion of a ventilator or flue and 3 an elbow mounted for rotary movement thereon and having preferably a ball bearing 4: on the upper portion of the ventilator. The upper end of the elbow is laterally turned to form a substantially horizontal extension 5 having an exit opening 6 through which the currents of air are discharged. It is my object in this invention to increase the natural suctionsor draft I inthe exit of the elbow, for'the purpose ofproviding better. ventilation in the room orspace with which the ventilator is connected, and with this end in view I provide a ring7, made preferably of sheet metal in the form substantially of a truncated cone. This ringencirclesthe end 5 of the elbow and projects Specification of Letters Patent. Patented Se Application fi1edJanuary25, 1917. Seriialii o. 144,335. IV

outwardlybeyond'the; exit opening therein, anarrow annular gap '8 being'xform'ed ,be-

tween: theconverging walls of. the ring"? and the edge. of the exit opening 6. iThering is of.clips 7-. The currents of airstriking ed by the wall thereof through the annular passage 8 and into the path'ofthe currents of air fiowing'from the ventilator, the inclination of the walls of the ring having the effect of directing the'air currents toward the center of the exit opening of the elbow. The end portion of the elbow encircled by the converging walls of the ring, is of uniform diameter so that the currents of air mounted on the elbow, preferably bymeans the inner surface of theringi will be directflowing through the elbow W111 not be rewithout choking or causing anyback prestheexit opening of the elbow, where'asufficient suction-will be formed todraw the tarded at any point, but mayvfiow freely i '75- 1 sure in-the elbow, and the tapered walls of the ring are parallel with a line drawn tan-, V 'gentially with respect to the end of '-the j f elbow to direct the currents of air flowing unobstructedair currents through the exit opening of the elbow.

For the purpose of hastening "the dis-- charge of the products of combustion andincreasing the suction in the ventilator, I'

prefer to provide means for imparting a" rotary-movement to the air currents, said means consistmg preferably of a series of blades 9 obliquely mounted on theinne'r;

surfaceof the cone shaped ring and extend-f ing from'end to end thereof. These blades and the smaller end of the ring 7 project 3 beyond the open end Gland the blades form passing through said ring and between said blades and to the air currents flowing from the flue, and increase the velocity of thejdiswith the ring and the wall of the flue a se- 'ries of narrow airpassages, the oblique archargeof' uchcurrents. The air currentsflowing out of the elbow and striking the walls thereof would be, under'ordinary con-.

7 ditions, retarded to a considerableextent by contact with such walls, but the revolving air currents willtset up such a suction at the mouth of the flue that the air discharged 1'10 from the flue will be drawn inwardly, away from the ventilator,--and the flowthrough the ventilator materiallyl 'hastened. The r l I blades 9 may be any suitable distance apart ed for rotary movement on a vertical axis and having an exit opening, a ring in the form of a truncated cone encircling the outer end of said elbow and said exit opening, the tapered walls of said cone being obliquely arranged with 'respectjto the end of said elbow-and spaced therefrom, an unobstructed annular air passage being thereby formed between said cone and elbow, the walls of said cone directing such air ourients inwardly to create a suction through in said elbow to prevent choking of the air currents passing therethrough, and substantially straight blades mounted obliquely on the inner surface of said cone and extending substantially from end to end thereof and converging from their rear toward their forward ends to impart a rotary movement to the currents of air passing between said cone and elbow. t

In witnes whereof I have hereunto set my -hand this 16th day of January, 1917.

' FRANK 0. SMITH." 

